How to Contribute

React Native is one of Facebook's first open source projects that is both under very active development and is also being used to ship code to everybody using Facebook's mobile apps. If you're interested in contributing to React Native, hopefully this document makes the process for contributing clear.

Our development process

Some of the core team will be working directly on GitHub. These changes will be public from the beginning. Other changesets will come via a bridge with Facebook's internal source control. This is a necessity as it allows engineers at Facebook outside of the core team to move fast and contribute from an environment they are comfortable in.

When a change made on GitHub is approved, it will first be imported into Facebook's internal source control. The change will eventually sync back to GitHub as a single commit once it has passed all internal tests.

Branch organization

We will do our best to keep master in good shape, with tests passing at all times. But in order to move fast, we will make API changes that your application might not be compatible with. We will do our best to communicate these changes and version appropriately so you can lock into a specific version if need be.

To see what changes are coming and provide better feedback to React Native contributors, use the latest release candidate when possible. By the time a release candidate is released, the changes it contains will have been shipped in production Facebook apps for over two weeks.

Bugs

We use GitHub Issues for our public bugs. If you would like to report a problem, take a look around and see if someone already opened an issue about it. If you a are certain this is a new, unreported bug, you can submit a bug report.

If you have questions about using React Native, the Community page list various resources that should help you get started.

Reporting new issues

When opening a new issue, always make sure to fill out the issue template. This step is very important! Not doing so may result in your issue getting closed. Don't take this personally if this happens, and feel free to open a new issue once you've gathered all the information required by the template.

One issue, one bug: Please report a single bug per issue.

Provide a Snack: The best way to get attention on your issue is to provide a reduced test case. You can use Snack to demonstrate the issue.

Provide reproduction steps: List all the steps necessary to reproduce the issue. Provide a Snack or upload a sample project to GitHub. The person reading your bug report should be able to follow these steps to reproduce your issue with minimal effort.

Try out the latest version: Verify that the issue can be reproduced locally by updating your project to use React Native from master. The bug may have already been fixed!

We're not able to provide support through GitHub Issues. If you're looking for help with your code, consider asking on Stack Overflow or reaching out to the community through other channels.

Security bugs

Facebook has a bounty program for the safe disclosure of security bugs. With that in mind, please do not file public issues; go through the process outlined on that page.

Pull requests

Your first pull request

So you have decided to contribute code back to upstream by opening a pull request. You've invested a good chunk of time, and we appreciate it. We will do our best to work with you and get the PR looked at.

Working on your first Pull Request? You can learn how from this free video series:

We have a list of beginner friendly issues to help you get your feet wet in the React Native codebase and familiar with our contribution process. This is a great place to get started.

Proposing a change

If you would like to request a new feature or enhancement but are not yet thinking about opening a pull request, we have a place to track feature requests.

If you intend to change the public API, or make any non-trivial changes to the implementation, we recommend filing an issue that includes [Proposal] in the title. This lets us reach an agreement on your proposal before you put significant effort into it. These types of issues should be rare. If you have been contributing to the project long enough, you will probably already have access to the React Native Core Contributors Facebook Group, where this sort of discussion is usually held.

If you're only fixing a bug, it's fine to submit a pull request right away but we still recommend to file an issue detailing what you're fixing. This is helpful in case we don't accept that specific fix but want to keep track of the issue.

Sending a pull request

Small pull requests are much easier to review and more likely to get merged. Make sure the PR does only one thing, otherwise please split it.

Please make sure the following is done when submitting a pull request:

All pull requests should be opened against the master branch. After opening your pull request, ensure all tests pass on Circle CI. If a test fails and you believe it is unrelated to your change, leave a comment on the pull request explaining why.

Note: It is not necessary to keep clicking Merge master to your branch on the PR page. You would want to merge master if there are conflicts or tests are failing. The Facebook-GitHub-Bot ultimately squashes all commits to a single one before merging your PR.

Test plan

A good test plan has the exact commands you ran and their output, provides screenshots or videos if the pull request changes UI or updates the website.

If you've added code that should be tested, add tests!

If you've changed APIs, update the documentation.

If you've updated the docs, verify the website locally and submit screenshots if applicable (see website/README.md)

If your pull request is merged, a core contributor will update the list of breaking changes which is then used to populate the release notes.

Copyright Notice for files

Copy and paste this to the top of your new file(s):

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/

If you've added a new module, add a @providesModule <moduleName> at the end of the comment. This will allow the haste package manager to find it.

Contributor License Agreement (CLA)

In order to accept your pull request, we need you to submit a CLA. You only need to do this once, so if you've done this for another Facebook open source project, you're good to go. If you are submitting a pull request for the first time, the Facebook GitHub Bot will reply with a link to the CLA form. You may also complete your CLA here.